/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    display: flex;
    min-height: 100vh;
    background-color: #f5f5f5;
    color: #333;
    transition: all 0.3s;
}

/* 侧边栏样式 */
.sidebar {
    width: 250px;
    background-color: #2c3e50;
    color: white;
    transition: all 0.3s;
    min-height: 100vh;
    position: relative;
    z-index: 100;
}

.sidebar-header {
    padding: 20px;
    background-color: #1a252f;
    text-align: center;
}

.sidebar-header h2 {
    font-size: 1.3rem;
    margin-bottom: 5px;
}

.sidebar-header p {
    font-size: 0.8rem;
    opacity: 0.8;
}

.sidebar-menu {
    padding: 20px 0;
}

.menu-item {
    padding: 12px 20px;
    cursor: pointer;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    border-left: 3px solid transparent;
    text-decoration: none;
    color: white;
}

.menu-item:hover {
    background-color: #34495e;
}

.menu-item.active {
    background-color: rgba(52, 152, 219, 0.2);
    border-left: 3px solid #3498db;
}

.menu-item i {
    margin-right: 10px;
    font-size: 1.1rem;
    width: 20px;
    text-align: center;
}

.menu-item span {
    font-size: 0.95rem;
}

.header h1 {
    font-size: 1.8rem;
    color: #2c3e50;
}

.card h2 {
    margin-bottom: 15px;
    color: #2c3e50;
    font-size: 1.4rem;
}

.card p {
    line-height: 1.6;
    color: #555;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: -250px;
        height: 100vh;
    }

    .sidebar.active {
        left: 0;
    }
}